Occupational asthma diagnosis

Sigsgaard T and Schlunssen V (2004) Occupational asthma diagnosis in workers exposed to organic dust. Ann Agric Environ Med ll(l) l-7... 

Moscato, G. et al., Occupational asthma a longitudinal study on the clinical and socioeconomic outcome after diagnosis, Chest, 115, 249, 1999. 

Cannon, J., Cullinan, P. and Newman-Taylor, A.J., Consequences of a diagnosis of occupational asthma A controlled study. Thorax, 49, 390P, 1994. 

Burge P, O Brien I, Harries M Peak flow rate record in the diagnosis of occupational asthma due to isocyanates. Thorax 34 317, 1979... 

Occupational asthma occurred in a pediatric nurse who had worked with hexachlorophene for 15 years (4). The initial symptom was rhinitis but at the time of diagnosis she was also suffering from attacks of asthma. 

Occupational asthma is an important source of adult-onset asthma in the community Once switched on, asthma does not, generally, go away. Although asthma improves after elimination or reduction of exposure to occupational sensitisers, studies report persistent symptoms in up to 100% of patients [7-13]. The chronic asthma remaining after cessation of exposure is usually of mild-to-moderate severity. Early diagnosis and early removal from exposure are good prognostic factors [7, 12]. Patients who remain in exposure may remain stable... 

Burge PS Single and serial measurements of lung function in the diagnosis of occupational asthma. Eur J Respir Dis 1982 63(suppl 123) 47—59. (NC)... 

Occupational asthma is potentially fatal. In two recent reports of deaths, the patients had remained exposed to the causal agents, TDI and flour, for economic reasons (Fabbri el al., 1988 Ehrlich, 1994). Care of a worker with a diagnosis of occupational asthma must therefore focus on eliminating exposure. Unfortunately, this often entails loss of employment. Patients who decide to remain in a job with exposure against medical advice can be supported by respiratory protection and medication but this must be accompanied by monitoring of symptoms, lung function and, where applicable, immunological responsiveness. 

Occupationally related airway diseases, including asthma and chronic obstructive pulmonary disease (COPD), have emerged as having substantial public he th importance. Nearly 30% of COPD and adult asthma may be attributable to occupational exposure. Occupational asthma is now the most frequent occupational respiratory disease diagnosis. More than 20 million U.S. workers are exposed to substances that can cause airway diseases. 

Foundry workers are exposed to diphenyl methane diisocyanate (MDI) and phenol formaldehyde and their decomposition products as well as to silica-containing particulates [7]. Compared with the controls, the foundry workers had more respiratory symptoms. They also had a significantly lower mean forced expiratory volume per 1 s (FEVi). Sensitization to MDI is the cause of asthma in foundry workers. However, the role of humoral immunological mechanism in MDI-in-duced asthma is unclear [8]. Carino [9] reported of an elder foundry worker who died while at work. His diagnosis was occupational asthma induced by MDI. 

Lung Function Tests 37 2.2.4.5.1 Diagnosis Methods of Occupational Asthma 54... 

Shortness of breath, cough, and wheeze are common symptoms of respiratory diseases (Table 3.2). These shared symptoms make misdiagnosis by physicians common if the diagnosis is based solely on reported symptoms. Medical tests help to distinguish the respiratory diseases from each other (Table 3.3). Other pitfalls in medical diagnosis include diagnosing common diseases (such as asthma, emphysema, and chronic bronchitis) instead of the actual rarer diseases (such as BO) and not considering occupational exposures as the cause. 

Other workers with flavoring-related BO were not appropriately diagnosed, even after reports of flavoring-related BO were published in the scientific literature (Kreiss et ah, 2002a Lockey et ah, 2002 Parmet and von Essen, 2002), public health commimications (CDC, 2002), and the press. Frequent misdiagnoses by physicians included asthma, bronchitis, and emphysema due to a presumptive diagnosis, an incomplete medical evaluation, and/or failure to make a coimection with occupational exposures. 

IV. Diagnosis requires a careful occupational history. Pulmonary function testing may document an obstructive deficit or may be normal. Variable airflow or changing measures of airway reactivity (methacholine or histamine challenge) temporally linked to exposure strongly support the diagnosis of isocyanate-induced asthma. 

---